Additive compositions to improve burning properties of liquid and solid



United States Patent 3 348 932 ADDHIVE COMPOSITIONS TO I1VIPROVE BURN- ING PROPERTIES OF LIQUID AND SOLID Ira Kukin, West Orange, N .J assignor to Apollo Chemical Corp., Clifton, N.J., a corporation of New York No Drawing. Filed Aug. 21, 1964, Ser. No. 391,303 9 Claims (Cl 444) This invention relates to compositions which are additive to liquid and solid fuels to improve their combustion properties. The additive compositions of the present invention are applicable to a variety of such fuels, including distillate fuels, residual fuels, coals or cokes, as well as gasolines and light hydrocarbon fuels such as jet fuels.

During the combustion of distillate fuels in domestic furnaces, diesel equipment, jet engines, vaporizing type burners, complete combustion of the fuel to CO and H 0 does not occur. Varnish-type deposits are left behind on the metal parts, and soot forms on the cooler portions of the furnaces and is also passed out the stacks. In a more general way, when burning any fuel, including the heavier liquid fuels designated as residual fuels as well as coals or cokes, it is equally desirable to improve the eificiency of the fuels by converting more of it to H 0 and CO and otherwise reduce the amount of soot and varnish that results from the incomplete combustion.

When used with residual fuels where high temperature slagging or corrosion may be the main problem and where an additive may be desired that raises the fusion point of the oil ashes containing vanadium and sodium in order to make these deposits more friable, the additive preparation described in the present invention may also often be used in order to serve as combustion catalysts to further improve the burning properties of the fuel proper, i.e. to improve the CO content of the flue gas and to reduce the amount of organic or carbonaceous material that would be left behind.

With coals or cokes the additive compositions described herein, either as a liquid or in the form of a dispersion or in the form of a powder that may be injected into the burner is desirable in order to reduce the carbonaceous, unburnt soot in the furnace.

With the lighter fuels such as aviation or jet fuels or naphthas or special distillates for gas turbines, the additive combinations will reduce coke and varnish deposits in the engines and exhaust parts.

The metallic combinations described in this invention when properly prepared with suitable anions or organically bonded materials will also find usage in gasolines to improve their burning properties,

It is known by those familiar with this art that organic compounds containing metals such as lead, iron, cobalt, manganese, copper, nickel and chromium can under certain conditions function as soot destroyers or combustion aids. The most potent of these are generally the iron, manganese and copper, but the introduction of the relatively large amounts of these metals to the fuel to give significant combustion improvement causes the fuels to become so unstable that in most cases it is impossible to utilize the catalytic properties of these metals. To offset Patented Oct. 24, 1967 the deleterious effect which these metals have on the fuels to which they are added, it has been proposed that one incorporate stabilizer or antioxidants to the fuel. The large amounts of stabilizer required, however, makes this approach economically impractical; also secondary effects take place such as rapid emulsification making the fuels thusly treated unmarketable.

The addition to the fuel of materials such as lead or cobalt soaps has been proposed to reduce soot. Their use is fraught with danger because of the large amounts of the lead and cobalt salts that are required to bring about any significant improvement in the soot forming tendencies. The heavy lead soaps settle out and also cause blockage of the fuel lines and rapidly clog the fuel filters and strainers. The other materials such as nickel, chromium, as well as metals such as zinc and tin that are sometimes mentioned in the literature are virtually inactive to bring about any significant combustion improvement.

Quite unexpectedly, I now find that I can utilize the metals mentioned above in such a way as to achieve pronounced improvement in the burning properties of the.

fuel without the deleterions side effects and at low cost, sufiicient to more than justify their usageLI have found that a small percentage of metal selected from one group consisting of iron, manganese or copper salts, when added to a larger amount of metal selected from another group that is less active catalytically as a combustion aid brings about a remarkable combustion improvement that is not obtained when using either group metal alone at the total metal concentration that is used in the combinations proposed. For the purposes of describing this invention I refer to the first group of metals consisting of the iron, manganese and copper compounds as the group A metals. The less active or inactive metals of the other group are referred to herein as the group B metals, and these in-' clude among others compounds of lead, cobalt, nickel. zinc, chromium, antimony, tin and vanadium.

To illustrate the dramatic improvement in the burning properties of the fuel when a combination of a metal from group A is made with a metal from group B in the proper proportions, I have prepared the following Table I in which the comparative effects of sample preparations wherein lead (of group B) and manganese (of group A) are added to a fuel singly or in the combination of the present invention. The percent soot reduction brought about by these metals is determined by a method described hereinafter. Not only is there a dramatic improvement in soot reduction when the combination of the present invention is used but perhaps of greater significance when utilizing this combination is that the overall soot reduction obtained is attained at a lower total .metal concentration in the fuel. The lowerthe concentration of added metals required in the fuel. to bring about economical and significant soot reduction, generally the less frequent are the problems that are introduced by way of instability or possible premature flash backs that sometime occur when the fuel contains a-high metal content.

TABLE I.TYPICAL EXAMPLES SHOWING IMPROVED BURNING PROPERTIES AND IM- PROVED STABILITY OF FUELS BY THE PRESENT METHOD Of group B 01 group A Gals. Addi- Percent Ex. percent by percent by tive to Gals. Grams Pb in Grams Mn in Stability of Reduction Weight Pb Weight Mn Fuel 1 Gal. Fuel 1 Gel. Fuel Treated Fuel in soot in Additive in Additive 3 COMMENTS TO TABLE 1 It can be seen above that whereas the addition of a lead compound to the fuel has soot reducing properties (70%), it causes some fuel instability because of the large amount of lead added to the fuel (0.068 gram/gal.). When, however, a small amount of manganese is added to the composition, as in Example 6, it is possible to reduce the total amount of lead to only 0.034 gram/ gals. of fuel with an 80% reduction in soot. The decreased lead concentration does not impair the fuel stability. By fuel stability,.I refer to the prevention of sludging and discoloration of the fuel and the plugging of fuel filters.

In the case of the other metals in group B defined herein such as zinc and tin, which have either no soot reducing properties or negligible soot reducing properties, it is possible by the co-addition of a group A metal (iron, manganese or copper) to effectuate good overall soot reducing properties in the fuel with good fuel stability. We cite the following examples to show the synergistic effect of a Group A metal (in this case-manganese), in combination with an inactive metal (in this case-zinc).

Grams Metal in 1 Gal. Fuel Percent Sample Containing Soot As shown above, the zinc by itslef is virtually inactive as a combustion catalyst, but in combination with manganese or iron, it is effective.

Another significant factor brought about by the use of a combination of a metal from group A and a metal from group B is that a lesser amount of stabilizer is required to prevent fuel instability. Since the stabilizers generally are expensive, this tends to make the use of these fuel additives described herein more economical. Moreover, overall better stability is achieved with this combination than would be possible regardless of how much stabilizer one would add, were it necessary to use a massive dosage of an active metal such as that described under group A.

To illustrate the various combinationsthat are possible and are included within the scope of this invention, a typical preparation is described below as Composition 1:

Composition I A fuel additive composition for use, mainly but not exclusively with distillate fuels such as home burner #2 fuel or diesel fuel, was prepared containing 5.6 percent by weight of lead derived from an oil soluble lead compound such as lead naphthenate or a lead tallate, 0.38 percent by weight manganese derived from an oil soluble manganese compound such as manganese naphthenate or tallate, 15 percent by weight of a stabilizer and sludge dispersing agent, and the remainder consisting of sludge solvents and viscosity reducing agents. This composition was added at a dosage of one gallon of additive to 8,000 gallons of a No. 2 distillate fuel. The latter was a blend of 65 percent by weight of catalytic cracked stocks derived from a Mid-continent crude and 35% by weight of virgin distillate fuel within the boiling range of 300 to 595 F. The thus treated fuel was combusted in a Delco #2 burner where the burner was adjusted to give an initial Shell-Bacharach Smoke Number of 5 at a C0 reading of Reduction 4 10 when the untreated fuel oil was burned in this burner. Under identical conditions when burning the abovetreated fuel oil, the Smoke Number was only 3.2 and the CO reading was 11.2, showing the improvement brought about by the above fuel additive composition.

To illustrate further the improved burning properties derived from this fuel additive composition, various combinations Were comparedin a laboratory test designed to measure the percent soot reduction effected by fuel additive compositions or components. In this test, a specific amount of treated and untreated fuel are separately burned off in dishes until the fuel no longer continues to burn, and unburnt soot and varnish remains behind in the dishes; the latter are then burned off in a high temperature oven at between 500 and 1,000 P. for a predetermined period after which the percent unburned carbon isrestimated visually or in some cases with a photometric scanning device. A soot reduction rating of indicates no soot or varnish left behind after the test period, and a rating at the other extreme of 0 indicating substantially no improvement in reducing soot by the additive composition. The above treated fuel by this test showed a rating of 75% (compared to 0 for the untreated fuel).

In the above fuel additive composition, in order to obtain therein 5.6% by weight of lead from lead naphthenate or a lead tallate, I use in the composition 23.3%

of naphthenate or tallate containing 24% by weight of lead, and in order to obtain 0.38% by weight of manganese in the additive, I use in the composition 6.35%

of manganese naphthenate or manganese tallate that con-,

tains 6% by weight of manganese. One gallon of the above treated fuel then contains 0.03 gram of lead and 0.002 gram of manganese, equivalent to 0.145 mole of lead and 0.036 mole of iron in 1,000 gallons of fuel.

As a further example, the fuel additive composition the same as for Composition I was used, but in this case one gallon of the additive composition was added to 4,000 gallons of Bunker C fuel that was burned in a low pressure, Babcock & Wilcox package, fire-tubed, boiler. A significant reduction in soot and slag was obtained with a reduction of stack temperature of over 400 F.

The stabilizers and dispersants that generally are desired to be coadded to the above beneficial. metallic combinations particularly for addition to the less stabledistillate or diesel fuels are any substances known to have such properties. Particularly effective are the ammonium, amine, hydroxyl amine, quaternary amine,calcium, magnesium, sodium, potassium, strontium, beryllium, zinc or barium salts of (a) tall .oil fatty acid, naphthenic acids, octoic or ethylhexoic acids, long chain or oil-soluble carboxylic (fatty) acids of natural or synthetic origin; (b) sulfonic acids of petroleum or synthetic origin; (0) oil-soluble alkyl phenols, as well as organic phosphorous compounds, phosphorous-sulphide treated olefins, non: ionic oil soluble surfactants and cationic oil-soluble surfactants, many of which are disclosed in British Patent 846,174 of Aug. 24, 1960; also oil-soluble amines and polymeric amides or similar polymeric stabilizers or dis persants such as are known to be used in the art as stabilizers and dispersing agents for fuel oils and lubricating oils.

OTHER COMPOSITIONS OF GROUP A AND GROUP B METALS Other compositions of the metals of group A with the metals of group B referred to hereinbefore were compounded in relative proportions similar to those above 5 indicated. Such other compositions are given in the 15 examples of the following Table II:

TABLE IL-FUEL ADDITIVE COMPOSITION Example Group A Percent Group B Percent N o. Metal(s) by Wt. in Metal(s) by Wt. in Additive Additive 0. 38 5. 6 0. 38 5. 6 0. 20 6. 3 0. 10 3. 2 0. 38 2. 3. 2 6 Iron 0. 19

1. 0 Iron 0. 10 7 plus 5. 6

Manganese 0. 28

5. 6 8 Iron 0. 19

0. 67 5. 6 9 Manganese- 0. 19

1. 0 1. 6 11 Iron 0. 10

0. 6 Iron 0. 19 3. 2 12 plus Manganese- 0. 10 g Manganese 0. 30 13 plus 2. 0

Iron 0. 08

14 Copper 0.10 2- 0 1. 34 Zinc 4 15 Manganese. 0. 38 plus Antimony 5. 4

These 15 compositions were blended with the fuel by similar method as that described with Composition I in the dosage proportions set forth in the following Table II-A, which table also shows the relative concentration of the metals in the fuel in terms of grams Weight and molar weight:

TABLE II-A Gals. Grams of Metal Added Moles of Metal Added Additive to 1 Gal. of Fuel to each 1,000 Gals. of Ex. Added to Fuel N0. Gals. of

Fuel

Group A Group B Group A Group B 1/8, 000 0. 002 0. 03 0. 03s 0. 145 1/8, 000 0. 002 0. 0a 0. 030 0. 145 1 8, 000 o. 0000 0. 034 0. 014 0. 154 1 4, 000 0. 001 0. 034 0. 01s 0. 104 1 4, 000 o. 004 0. 01s 0. 072 0.28 1 4000 0.002 g ggg 0. 035 8&2: 0.0005 0. 0095 l/sooo 0.0015 0.0205 323g 1 4000 0. 002 8 8 0.030 0:050 1 4000 0. 002 8 88 0.036 833% 1/4000 0.001 8:853 0. 01s 8 3g 11 1 4000 0. 001 g: 0. 01s 8:?8 0. 002 0. 034 0. 030 0. 104 12 000 i 0. 001 0. 055 0. 018 egg Whereas the metal combinations disclosed in Composition I and in Table II are used primarily with distillate or diesel fuels, they can be used equally Well with residual fuels. Because of the greater soot problem in burning a residual fuel, particularly Bunker C fuel, as a general rule-of-thumb, one doubles the concentration that would be used with the lighter distillate fuels. In Table II the preparations designated as 8 and 9 could be used as such with residual fuels. In the other examples 2 l to obtain the maximum benefits from this invention, it is advisable to use double the concentration of additive as that shown in the table.

Although these compositions of Table II are intended to be used primarily for aiding combustion, some of the combinations would be of importance also to reduce corrosion and slagging. The composition of Example 15 would be particularly suited for additionally reducing low temperature sulfuric acid corrosion of boilers because of the combination of the zinc and antimony with the manganese.

The metals in group A of Table'II are most readily derived from the following: iron from iron naphthenate containing 6% iron by weight, from iron tallate containing 6% by weight of iron, and from iron octoate containing 6% by weight of iron, the octoate being preferably derived from ethyl hexoic acid; manganese from manganese naphthenate containing 6% manganese by weight, from manganese tallate containing 6% by weight of manganese, and from manganese octoate containing 6% by weight of manganese, the octoate being preferably derived from hexoic acid; copper from copper naphthenate containing 8% copper by weight, from copper tallate containing 8% by weight of copper, and from copper octoate containing 8% by weight of copper, the octoate being preferably derived from ethyl hexoic acid.

The metals in group B of the table are most readily derived from the following: lead from lead naphthenate containing 24% lead by weight, from lead tallate containing 24% by weight of lead, and from lead octoate containing 24% by weight of lead, the octoate being preferably derived from ethyl hexoic acid; cobalt from cobalt naphthenate containing 6% cobalt by weight, from cobalt tallate containing 6% by weight of cobalt, and from cobalt octoate containing 6% 'by weight of cobalt, the octoate being preferably derived from ethyl hexoic acid; zinc from zinc naphthenate containing 8% zinc by weight, from zinc tallate containing 8% by weight of zinc, and from zinc octoate containing 8% by weight of zinc, the octoate being preferably derived from ethyl hexoic acid; nickel from nickel naphthenate containing 6%. nickel by weight, from nickel tallate containing 6% by weight of nickel, and from nickel octoate containing 12% by Weight of nickel, the octoate being preferably derived from ethyl hexoic acid; chromium from chormium naphthenate containing 6% chromium by weight or from chromium acetylacetonate containing 14.9% chromium by weight; antimony from antimony naphthenate containing 14% antimony by weight or antimony octoate containing 26% antimony by weight; tin from tin naphthenate containing 14% tin by Weight or from tin octoate containing 28% tin by weight; and vanadium from vanadium naphthenate containing 4% vanadium by Weight or from vanadium acetylacetonate containing 10% vanadium by weight.

To show further that smaller amounts of metal are required by the method and product of this invention, 1

list in the following Table III the concentration of metals that have been described in the prior art and are known to others and I compare this concentration with the amounts required by the practice of this invention when the additives are used with fuels of the present invention.

TABLE III.-RANGE OF GROUP A METALS FOR COMBUS- TION IMPROVEMENT Note.In each example above, the lower value generally sutfices for distillate fuels and the higher value would be used with residual fuels.

Likewise in the following Table IV, the concentration of metal of the group B type used in the prior art are compared with their concentration required or permitted by the practices. of the present invention, illustrating the tremendous economies afforded by the present invention.

TABLE IV.RANGE OF GROUP B METALS FOR COMBUS- TION IMPROVEh/IENT As Used Heretofore As Used Here in Conjunction Wigh Group A Metals Grams Metal Moles Grams Metal Moles of in Gallon Metal in in Gallons Metal in Fuel 1,000 gals fuel 1,000 gals.

in fuel 0. 09-0. 30 0. 45-1. 35 0. 025- 15 O. 13 0. 68 0. 026-0. 08 0. 45-1. 35 0. 008-0 04 0. 13-0. 68 0. 026-0. 08 0. 45-1. 35 0. 008 0. O4 0. 13 0. 68 0. 029 0. 09 0. 45-1. 35 0. 0085-0. 045 0. 13-0. 68 0. 024 0. 07 0. 45 1. 35 0. 0068 0. 035 0. 13-0. 68 Antimony- 0. 016-0. 08 0. 13-0. 68 Vanadium. 0. 0066-0. 035 0. 13-0. 68 Tin 0. 0155-0. 081 013-0. 68

1 No previously known reference to use of these metals for improving burning properties of fuel oils, Whereas in the case of Lead, Cobalt, Nickel, Zinc and Chromium, some limited success has been reported with their use at the high dosages.

The purpose for Tables III and 1V is to show that by comparison to the amount of metals previously claimed to be effective, or described in the literature, I find that when we use the combinations. as described herein, the total amount is considerably less than that previously found to be effective; yet I obtain better combustion improving results at a lower total metals content. Inother words Tables III and IV illustrate the workings of my present invention, i.e. where we are concerned primarily with improving the combustion properties of distillate fuel, by using the combination of group A and group B metals I improve the combustion at a lower total metal content than heretofore, defined either in grams of metal per gallon fuel or in moles per 1,000 gallons of fuel.

The moles of metal as referred to in this application are the gram equivalent atomic weights of the metals specified herein, i.e. one mole of lead would weight 207.2 grams.

The following Tables V, VI and VII further explain the scope of the invention by giving the broad range and the preferred range of the group A and group B metals, considered conjointly and separately, in 1000 gallons of the various fuels to which the invention is particularly applicable.

TABLE V.-RANGES FOR GROUP A AND GROUP B METALS WHEN USED PRIMARILY FOR COMBUSTION PROBLEMS Total Moles of Group A and Group B Metals in 1,000 Gallons Fuel.

In the above with liquid fuels I have cited the ranges as moles of metal in 1,000 gallons of fuel. This. is equivalent approximately to moles of metal/8,000 lbs. of liquid fuel (depending upon the exact gravity of the fuel). For this purpose the equivalent ranges with solid fuels would be: moles of metal/11,000 lbs. of solid fuel.

TABLE VI.RANGES FOR GROUP A METALLIC ACTIVA- TORS WHEN USED IN CONJUNCTION WITH GROUP B METALS-PRIMARILY FOR COMBUSTIONPROBLEMS In the above with liquid fuels we have cited the ranges as moles of metal in 1,000 gallons of fuel. This is equivalent approximately to moles of metal/8,000 lbs. of liquid fuel (depending upon the exact gravity of the fuel). For this purpose the equivalent ranges with solid fuels would.

be: moles of metal/11,000 lbs. of solid fuel.

TABLE VII.RANGES FOR GROUP B METALS WHEN USED WITH GROUP A METALLIC ACTIVATORS-PRIMARILY FOR COMBUSTION PROBLEMS Moles of Group B Metals in 1,000 Gallons Fuel Broad Preferred Range Range 1 All fuels. 0. 001-2. 5 0. 04-1. 8 2. Residual fuels (and equivalent when 0. 005-2. 5 0. 075-1. 3

used with Coals, Cokes, Lignites, Peat or Bagasse) 3 Distillate fuels 0. 001-1. 3 0. 04-0. 65

In the above with liquid fuels we have cited the ranges as moles of metal in 1,000 gallons of fuel. This is equivalent approximately to moles of metal/8,000 lbs. of liquid fuel (depending upon the exact gravity of the fuel). For this purpose the equivalent ranges with solid fuels would be: moles of metal/11,000 lbs. of solid fuel.

METHODS OF EVALUATING EFFECTIVENESS OF- ADDITIVE COMBINATIONS The effectiveness of the specific combinations described herein can be demonstrated by a wide variety of methods, some of which are:

(1) When a #2 warm air furnace, typically with a rated capacity of 0.75 g.p.h. firing rate, one determines the percent CO content of the stack gases with the furnace set initially at a Bacharach Smoke Number of from 1 to 3. The beneficial additives described herein under this test condition all showed higher CO contents of from 1 to 3.75%.

(2) With the same test conditions as in above,'one determines the temperature of the stack gases with and without the treated fuels containing the additive combinations described herein. In each case, the additive combinations reduced the stack temperature by from 25 to F. This indicates that less excess air was needed to obtain smoke-free combustion showing that the furnace is operating at greater efficiency.

(3) Run the furnace under smoking combustion conditions with the blower or damper open so that insufficient air is available for complete combustion giving an initial smoke number with the untreated fuel of 4 to 5. Under the same conditions the treated fuel results in smoke numbers of 2 to 3 /2 when the beneficial compositions described herein are added to the fuel.

(4) Field trials in which a selected number of homes are run with the additive treated fuel as compared to a similar number of homes using untreated fuel. In each case after periods of 2 weeks to six months, there was considerable less soot present in the backsides and the stacks of the furnaces, with considerably cleaner appearanee of the smoke exhausting through the stacks.

(5) Field trials in which a number of diesel buses or diesel trucks are operated with diesel fuel and as a control a stipulated number of vehicles are operated with the additive-treated diesel fuel. The smoke numbers of the exhaust gases are determined or estimated visually.

9 In each case, there was a significant reduction of the smoke number in the exhaust gases from the treated fuels.

(6) In laboratory single or multi cylinder diesel engines where smoking conditions prevail, such as under full load or during overloading, simulating stop and go acceleration or hill climbing. With the beneficial additives described herein reduction of smoke numbers of from 3 to 4 /2 units were realized, showing increased thermal efficiency of the diesel engine.

(7) In laboratory crucible tests where the fuel oil is burned off under atmospheric conditions, after which the resultant soot residue is ignited in a muffle furnace at a predetermined temperature. Under identical conditions, the fuel treated with the additive compositions described herein showed a greater reduction in soot (from 50 to 95%) during a predetermined firing period. Moreover, by this test, significantly lower amounts of additives-i.e., moles of metal in 1,000 gallons of fuel, were required to improve the combustion properties of the fuel as compared to the previously required additive concentrations to achieve the same improvement, but which at the same time have undesirable side effect.

(8) Pictures of flame patterns-with this invention, the flame is longer, more uniform, brighter and less spurious.

CHEMICAL COMPOSITION OF BENEFICIAL METALLIC CONSTITUENTS The particular form of the metallic compounds utilized for the purpose of this invention can influence the stability of the additive preparation and particularly determines the storage stability of the fuel to which these metallic compounds are added. The stability of the compounded fuel oils are in turn effected by the composition of the fuel oil itself and it is known that certain unstable constituents in fuel oil that cannot always be refined out lead to storage instability of the fuel oil.

It frequently is possible to correct for some of the instability brought about by the metallic soot destroyers by judicious selection of antioxidants or dispersant-stabilizers. In any case, the less the tendency of the metallic catalyst to cause the fuels to become unstable, the smaller the quantity of stabilizer required. Since the latter are generally expensive, and may also lead to undesirable side effects such as emulsification or secondary interac tions with minor polar constituents in the fuel, it is desirable to use that anion or the metallic combinations that have the least effect on the instability of the fuel. In other cases, where the additives are intended primarily for residual fuels or coals, the choice of anion may be somewhat less critical and the choice then is' governed by the least expensive anion.

In other cases where the metallic additive is used with another liquid product such as gasoline, light jet fuel or in a material other than a fuel, the choice of anion is generally governed by the solubility of the metallic combinations in the particular vehicle to which it is added.

Without in any sense limiting the general applications for the metallic combinations described herein, one or more of the following anions can be employed to prepare the metallic combustion aids described herein, in addition to others that would be familiar to those knowledgeable in this art. These anions may also be employed to prepare the dispersing agents that are used herein in combination with the metallic combustion aids. The nonlimiting anions are oleates; tall oil fatty acids, naphthenates; phenolates and alkylated phenolates, sulfurized phenolates, formaldehyde-polymerized alkyl phenolates; ethylhexoates, octoates, carboxylates of natural or synthetic origin; alkyl aryl sulfonates of natural or synthetic origin; organic phosphates and phosphonates; glyco or glycerol or polyhydroxy or multihydroxy aromatic borate complexes; cyclo and dicyclopentadienyls; chlorinated dicyclopentadienyls; cyclo and dicyclopentadienyl carbonyls and halides; carbonyls having sufficient solubility in the medium employed; acetyl actonates; polyamine aldehyde or salicyaldehyde complexes such as N,N -disalicylidene-1,2-ethanediamine; glycerides and their derivatives; and alkyls or aryl alkyls having a direct metal to carbon bonding.

In the case of additive compositions to be used with coals or cokes, it is possible to utilize the combinations described in this invention in the form of powders wherein the metals are present either as oxides, hydroxides, carbonates, silicates, aluminosilicates and other naturally occurring or synthetically prepared inorganic compounds or complexes containing the specified metals, as Well as the powdered metals themselves.

When used with residual fuels the above inorganic compounds or complexes can either be used as such or in the form of slurry or dispersion of the active constituents in an oil phase as Well as an aqueous emulsion, etc.

Other materials may be used with the practice of this invention. To those familiar with the art it is known that many chlorinated compounds improve the soot destroying properties of metallic additives such as described herein. In any case the additive of a chlorinated compound added to any of the beneficial combinations described herein is not only possible but in many cases highly desirable. The exact amount of chlorinated compound to use will depend upon the particular application involved and whether or not there are any undesirable side reactions that might affect adversely the application of the metallic combination when used with the chlorinated hydrocarbon. For example in those furnaces where any evolution of even trace amounts of hydrogen chloride would prove deleterious, then one would not add any chlorinated hydrocarbon to the additive compositions described here. The range of the chlorinated hydrocarbon to be used would be such as to provide from 0.1 to 3.0 parts by weight of chlorine for each 3.5 parts by weight of lead, or equivalent total molar amount of any of the other metals described herein, in the additive, where the latter is added to the fuel at a treatment rat of one gallon to each 4,000 to 8,000 gallons of fuel, or equivalent in the case of coals or cokes, or where the compo sitions are used as burner cleaners. A preferred range of chlorine would be 0.75 to 1.4 parts of chlorine for each 3.5 parts of lead or equivalent when used as described above.

Frequently it also is desirable to add certain penetrating solvents to these fuel additive compositions in order to promote the effectiveness of the dispersants contained therein in dissolving or loosening sludge that may be present in the fuel storage tanks, in the fuel lines, on the strainers, nozzles or screens of a furnace. It is also possible that these penetrating agents in some unexplained Way promote the effectiveness of the combustion combinations described herein, either by promoting atomization or in another fashion. Notwithstanding how these solvents function, several that I have used may be cited but without limiting this invention to the specific cited examples as follows: aromatics, ketones, aldehydes, alcohols, sulfones and sulfoxides, ketone-alcohols such as diacetone alcohol, organic phosphorous-containing solvents, amine solvents including polyfunctional nitrogen-containing compounds such as dimethylformamide and its derivatives, specific solvents such as the Carbitols and Cellosolves (Union Carbide), dimethylacetamides, and comparable materials produced by other companies; also brominated or even florinated solvents in addition to the chlorinated solvents described above.

Biocides may also be incorporated in the fuel additive combinations of the present invention. In order to prevent bacterial growth or slime formation in fuel tanks which would lead to rapid filter plugging, it is known to those 1 1* familiar with the art that certain bactericides and germicides can be added to the fuel or to the water-bottoms in the fuel tanks. Indeed these materials can be incorporated into an additive composition containing these metallic combinations. Without limiting to the following, we have incorporated materials such as parachlorophenols and their derivatives, paranitrophenol, quarternary and cationic germicides and specific agents such as. 3,5-dimethyltetrahydro 1,3,5,2H-thiadiazine-Z-thione. The above are cited merely, as examples and for a complete list of bactericides and germicides that one can add to this combustion type additive for addition to fuels any standard reference on bactericides and fungicides can be consulted. The only limiting factor would be solubility of the particular agent in the medium to which the fuel composition would be added when the agent is incorporated into the fuel additive.

In many burners or in gas turbines, there frequently is a problem that arises because of the slagging tendencies of residual fuels containing vanadium, sodium and sulfur compounds which tend to form a sticky and highly corrosive slag on the hot metal parts within the burner, as well as on the refractory brickwork. A great many slaginhibiting materials are cited in the literature and patents, generally consisting of compounds or combinations containing magnesium, aluminum, calcium, silicon and ,zinc among others. It frequently ispossible to incorporate the additive combinations of the present invention as soot destroyers or combustion catalysts in combination with the anti-slagging compounds that are known to be effective for this purpose and such combinations would be included within the scope of this invention. As a matter of fact, frequently the coaddition of the combustion aids cited herein act as synergistsfor the anti-slagging additives, and such combinations form a part of a copending patent application.

PREPARATION OF THE METALLIC ADDITIVES. The preparation of the various iron, manganese, lead or other metallic soaps or compounds that can be used as the metal compounds in the combustion aids of the present invention are available in standard reference texts.

' about 210 to 240 F. for a period of time suflicient to react the lead oxide with the fatty acid, dehydrating under vacuum or by other means and then filtering. 'In other cases such as in preparing an iron naphthenate, a sodium.

salt of naphthenic a'cid would first be prepared by adding 100 grams of sodium hydroxide to 150 grams of naphthenic acid of 230 milligrams KOH of acidity, followed by addition of 170 grams of mineral spirits, 250

grams of water and after heating to about 150 F. adding 75 grams of a 20% solution of a ferrous sulfate heptahydrate and mixing until an emulsion forms, removing the aqueous. layer and dehydrating the oil layer remaining followed by filtration. The methods for preparing metallic alkyl phenates or their derivatives, for use either as the combustion additive of .this invention or as a barium or calcium stabilizer or dispersing agent can be prepared by methods as described in US. Patents #2,406,564, #2,402,- 448, #2,943,053,. #2,785,131, or #2,420,893. Typical preparations for an oil soluble sulfonate dispersant are described in US. Patents #2,924,618, #2,924,617, or #3,005,847. A typical preparation for preparing a cyclopentadienyl salt that may be used in the practice of this invention is described in U.S.-Patent #2,983,741.

Whereas the practice of this invention can be carried out by mixing in a batch or continuous process the spe' cific components such as are described in Composition 1, it is even more advantageous to prepare the combustion additives together with the dispersant-stabilizers in-situ in the reaction kettle. Apparently the dispersant-stabilizer acts to reduce oxidation or polymerization of the metallic combustion aid, thus furthering its subsequentutilization. Also, the dispersant if present initially results in higher yields of product making it more economical to produce. Finally, by this method, new and unpredictable combinations have resulted that appear to have increased benefits and which cannot be attained by blending of components.

Metallic salts containing lead, iron, manganese, or many of the metal combinations cited herein tend to become unstable when moisture or water is permitted to penetrate a mixture of these metallic compounds in an organic solvent such as mineral spiritsor hydrocarbon oil. Itis withinthe scope of this invention to add one or more drying agents or humectants that would tend to absorb any adventitious water by chemical means or by physical means. For this purpose glycols and Cellosolves can be used, organic agents which when they react with water are transformed into otherorganic compounds that use up this water but are in themselves not harmful to the stability of the metallic additives.

Whereas this invention is described generally as being of use for liquid fuels or coals, .it is possible to utilize these combinations in other Ways, some of which are cited below:

One such example is a burner cleaner where periodically a mixture of these metallic combustion compounds in a solvent is passed through a furnace'under ignition conditions thusly coating the ash or carbon soot that has built up within the furnace. The. soot and carbon particles are thusly burned off at lower temperatures that otherwise prevail in these cooler sections of the furnace where the soot has been accumulating. In other words, the periodic use of this burner cleaner is a substitute for periodic vacuum cleaning of the furnace. Likewise a similar combination could be used in the same fashion to periodically clean out carbon deposits from diesel and jet engines. For this application as a burner or engine cleaner, the dispersant or stabilizer in the additive prepared as in accordance with Composition I would be replaced either entirely or in part with a penetrating solvent containing alcohols, or ketones, or aromatics, or chlorinated hydrocarbons, or phosphorylated hydrocarbons, or aldehyde solvents including dimethylformamide, as well as combinations thereof. The incorporation of a polar solvent would be to give solvent properties to the burner cleaner that would permit it to dissolve out sludge, gums and varnish from the lines and screens.

In other than fuel applications, these combinations can find application as extreme pressure agents in grease lubricants, as rust and corrosion inhibitors, as driers for coatings.

I claim:

'1. A fuel additive composition to improve the combustion of the fuel by reducing soot, consisting essentially of the addition to an amount of 1,000 gallons or its equivalent of the fuel of the admixture combination of:

(A) Metal selected from the group consisting of iron,

manganese. and copper, and (B) Metal selected from th group consisting of lead, cobalt, nickel, zinc, chromium, antimony, tin and vanadium, the metal concentration in the composition of the metal of group A being less than the metal concentration of the metal of group B, and in the following amounts, proportions and relative proportions in said stated amount of the fuel: the metal concentration of the metal of group A being in the range of from 2 1()- to 1.35 moles of the metal, and the metal concentration of the metal of group B being in the range of from 0.001 to 2.5 moles of the metal.

2. The fuel additive composition of claim 1 in which for a distillate fuel of the stated amount the metal concentration of the metal of group A is in the range of from 2x10" to 0.7 moles of themetal, and the metal con- 1.3 centration of the metal of group B is in the range of from 0.002 to 1.4 moles of metal.

3. The fuel additive composition of claim 1 in which the metals of group A and group B are derived from oil soluble compounds of the metals.

4. The fuel additive composition of claim 1 in which for a residual fuel of the stated amount the metal concentration of the metal of group A is in the range of 1 1O to 1.35 moles of the metal, and the metal concentration of the metal of group B is in the range of 0.01 to 2.7 moles of the metal.

5. A fuel treated to improve its combustion property, and particularly the reduction of soot, consisting essentially of a fuel in an amount of 1,000 gallons of the fuel or its equivalent and an additive composition admixed therewith, the additive composition comprising an admixture combination of (A) Metal selected from the group consisting of iron,

manganese and copper, and

(B) Metal selected from the group consisting of lead,

cobalt, nickel, zinc, chromium, antimony, tin and vanadium, the metal concentration in the composition of the metal of group A being less than the metal concentration of the metal of group B and in the following amounts, proportions and relative proportions in said stated amount of the fuel: the metal concentration in the fuel of the :metal of group A being in the range of from 2 10 to 1.35 moles of metal added to 1,000 gallons of the fuel, and the metal concentration in the fuel of the metal of group B being in the range from 0.001 to 2.5 moles of metal added to 1,000 gallons of the fuel.

6. A fuel according to claim 5 in which the metal concentration in the said stated amount of the fuel of the metal of group A is in the preferred range of from 0.0025 to 0.4 moles of metal, and the metal concentration in the said fuel of the metal of group B is in the preferred range of 0.05 to 1.4 moles of metal.

7. The fuel additive composition to claim 1 in which the metals of group A and group B are selected from the group consisting of the said metals in powdered form, their oxides, hydroxides, carbonates, silicates, and aluminosilicates.

8. The fuel additive composition of claim 7, wherein said powders are in the form of a dispersion in an oil or solvent carrier.

9. The fuel oil additive composition of claim 7 in the form of a water-in-oil dispersion of the powdered metals.

References Cited UNITED STATES PATENTS 2,013,152 9/1935 Hoyt 4451 2,014,686 9/1935 Lubovitch et al. 444 2,059,388 11/1936 Nelms 445 2,369,024 2/ 1945 Crecelius 44-4 2,781,005 2/1957 Taylor et al. 4467 X 3,002,826 10/1961 Norris 4467 X 3,078,665 2/1963 Rocchini et al. 444 X FOREIGN PATENTS 8,701 8/1911 Great Britain.

DANIEL E. WYMAN, Primary Examiner.

C. F. DEES, Assistant Examiner. 

1. A FUEL ADDITIVE COMPOSITION TO IMPROVE THE COMBUSTION OF THE FUEL BY REDUCING SOOT, CONSISTING ESSENTIALLY OF THE ADDITION TO AN AMOUNT OF 1,000 GALLONS OR IT EQUIVALENT OF THE FUEL OF THE ADMIXTURE COMBINATIN OF: (A) METAL SELECTED FROM THE GROUP CONSISTING OF IRON, MANGANESE AND COPPER, AND (B) METAL SELECTED FROM TE GROUP CONSISTING OF LEAD, COBALT, NICKEL, ZINCH, CHROMIUM, ANTIMONY, TIN AND VANADIUM, THE METAL CONCENTRATION IN THE COMPOSITION OF THE METAL OF GROUP A BEING LESS THAN THE METAL CONCENTRATION OF THE METAL OF GROUP B, AND IN THE FOLLOWING AMOUNTS, PROPORTIONS AND RELATIVE PROPORTIONS IN SAID STATED AMOUNT OF THE FUEL: THE METAL CONCENTRATION OF THE METAL OF GROUP A BEING IN THE RANGE OF FROM 2X10**5 TO 1.35 MOLES OF THE METAL, AND THE METAL CONCENTRATION OF THE METAL OF GROUP B BEING IN THE RANGE OF FROM 0.001 TO 2.5 MOLES OF THE METAL. 